VIX back above 15 as stocks slide

The S&P 500 was down 9.77 percent to close at 1646.06. That is the lowest close since July 8 and broke another level of support. Resistance is at 1700 and support at 1600.

The Nasdaq 100 lost 4.15 points, or 0.14 percent, to finish at 3069.75. It has held up better than its peers and was positive for much of the day. It has resistance at 3100 and first support at 3030.

The Russell 2000 lost 11.05 points, or more than 1 percent, to end at 1013.25. It is closely following the SPX at this time. Like the SPX and NDX, the small-cap index steadily fell through the afternoon and finished at session lows. It has resistance at 1055 and support at 1000.

The VIX was up 0.73 points, or 5.08 percent, to 15.10. The implied-volatility index was just off its high of the day, which came just before the bell. It remains significantly higher than actual volatility, as the 10- and 20-day historical volatility readings for the SPX are both around 8 percent.

The VIX futures followed higher. The August futures, which only have one day left to trade before settlement, were up 0.60 points to 15.05. The September futures gained 0.35 points to close at 15.95. That had the iPath S&P 500 VIX Short-Term Futures Note (:VXX) up 2.81 percent to $15.39.